We lived in the Houston area when we began homeschooling, and most of the other homeschoolers we knew couldn't afford private school. We knew a few people that homeschooled for religious reasons. (I have not found the stereotype of ultra-religious, sheltered homeschooled kids to be particularly accurate.) Living in Colorado, it's often just more practical to homeschool in the more rural areas since the children might spend an hour or more on the bus each way.
Due to COVID, the majority of us are homeschooling now anyway
Teachers provide remote education, but the real truth is that the overwhelming majority of kids need in-person supervision to get any actual work done. My oldest child was supposed to attend public high school this year, but it has been online. And he needed tech support from me the first few weeks. My other two are homeschooling, and I have been regularly babysitting a fourth child, a little girl whose mom is a single parent.